Coupling



Oct. 6, 1942. w FLATFORD 2,297,828

COUPLIN G Filed May 12, 1941 2 Sheets-Sheet l RECORDING q APPARATUS INVENTOR W. R. FLATFORD Oct. 6,- 1942. w. R. FLATFORD COUPLING Filed May 12, 1941' 2 Sheets-Sheet 2 INVENTOR W. R. FLATFORD BY. A015?? Patented Oct. 6 'lQ42 to Phillips Petroleum Company,

of Delaware a corporation Application May 12, 1941, Serial No. 393,101

2 Claims. (01. 173-328) This invention relates to a coupling 'member for establishing electrical and mechanical connection between the electrodes and the electrical cables in well logging apparatus.

The present invention provides a coupling member by which various arrangements of electrodes may be used with the same electrical cable. cable may be quickly attached or detached from an electrode assembly allowing the operator to choose the arrangement of electrodes best suited to the conditions in the well bore to be logged. Coupling devices for joining a cable to an electrode present a mechanical problem not encountered ordinarily in making electrical connections under less severe conditions. The well bore in which electrical logging is carried out usually contains water'or drilling fluid which is electrically conductive and is under high pressures; in many cases pressures on the order of thousands of pounds per square inch are encountered. Leakage of the fluid; into a coupling member causes shorting of the electrical circuit. and makes the electrical logging records worthless. Not only must the coupling member be fluid tight under high pressures, but it must also be so constructed'as to carry the weight of the electrode assembly'and properly distribute the weight on the electrical cable. The present invention provides a cable coupling device which is especially useful for joining. well log ing elec-.

trodes to the electrical cable connecting the electrodes with equipment at the surface of the earth.

An object of this invention is to provide a coupling device for making connection between the well logging electrodes and the electrical cable in electrical logging apparatus.

Another object of this inventionis to provide sucha coupling device which will be fluid-tight under the pressure existing in a well bore Other objects and advantages will be apparentfrom the detailed description and accompanying drawings. 1.

Figure 1 is an elevational view, partly in cross section, of the well logging electrodes and the coupling suspended in a well'bore.

Figure 2 is a cross sectional view, of the coupling member. v

With reference to Figure 1 of the drawings the numeral! designates the well bore into which an electrical logging electrode assembly issuspended by means of a cable 6 containing a plurality of electrical conductors. The cable may be ex- By means of the coupling member the a suitable cable reel I at the surface of the earth. The metallic electrodes comprising a lower electrode 8, a middle electrode 8 and an upper electrodev iii, are spaced along a tubular support ll of suitable electrical insulating material, for example, fabric saturated; with resin. The electrode assembly is made up of the three electrodes, longitudinallyspacedeach from the other along the well bore to give, insofar'as possible, 10 the desired penetration of electrical current into the earth formations adjacent to the bore hole. The drilling fluid or other liquid in the well bore makes contact with the electrodes through the holes [2 in the supporting member I l. The bottom of the tubular supporting member H is closed by the plug. it. The electrodes are in electrical communication with conductors in cable 6 through means of. the electrical conductors ll, l5 and it which are connected to the conductors of cable 6 through electrical contacts within the housing, i I of the coupling mem-' her. The electrical conductors contained in the /cable 6 are connected to suitable recording apparatus l8 and incidental equipment, not shown 5 in the drawings, by conductors i9, 20 and 2| through slip ring and brush connections 22, 23 and 24 on the cable reel.

body or the couplingmember consists of a male member 25 and a female member 26 which are complementary and are joined together by screw threads when the coupling is made up as in the figure. The femalemember-is protected from contact with fluid in the well bore by the elec-'- trically insulating housing [1 previously referred t'oin connection with Figure 1. The exterior upper part of the female member into the com-' partment' 34 in the interior of the coupling. Leakage of the well fluid into the interior of the coupling past the cable 6 is prevented by the resilient packing 35 which is held in position by the packing gland 3G. The cablet terminates in tended or retracted in the well bore by means of 5 the compartment I4 inside a sleeve 11 of elec- With reference to Figure 2 of the drawings, the

of the male member is similarly protected frond 4 I contact with the well fluid by the covering 21 of trical insulating. material. The central, or weight carrying conductor 30 extends through sleeve 31 and the plug 38 to which the conductor is attached. I The weight of the electrode assembly and of the coupling is ecarried by the cable 30 through the means of the weight supporting member consisting of the sleeve 31 and plug 38.

The sleeve 31 of insulating material is under a compression load and is thus capable of supporting the weight imposed upon it by the electrode assembly and the coupling. I

Electrical conductors l4, l and lb extend through the lowervpart of the male member 2-5 of the coupling and terminate in jacks 48, ll and 42 mounted in the male member, and insulated therefrom, by electrical insulating disk 43. Leakage of'well fluid into the interior of the coupling member at the point of entry of the conductors I4, 45 and I 6 is prevented by the resilient paokings I4 and packing glands '45. The electrical connection between the insulated conductors H, i5 and I6 and the conductors 30, 3! and 32 of the cable 6 is made through the Jacks and the corresponding pins 46, 41 and 48. The pin 41 is attached to the conductor 30 at the plug 38 by means of the insulated lead it.

Pins 46 and 48 are connected to conductors 32 The coupling is easily taken apart or put to gether allowing electrode assemblies to be quickly changed or the electrical connections readily irrspected. To take the coupling apart, the packing gland 36 is unscrewed to release the packing I5 and allow freedom of movement between the 5 female portion of the coupling and the cable 8. The female and male members are then parted at the screw threaded joint and the female member moved along the cable. The insulating sleeve 31 and the plug. 38 are not attached to the member 26 but remainat the end of the cable 6. The pins 46, 41 and 48 can then be removed from the corresponding jacks 40, 4|, and 42 and the electrical circuit broken.

To assemblethe coupling, the pins 46, 41 and 48. are inserted in the jacks, the male and female members .25 and 26 oi the coupling screwed together, and the packing gland 3t screwed into place. I

While I have herein shown and described a preferred embodiment of my invention, it is understood that various changesmay be made in the size, shape, and relative positions of some of the parts of the device without departing from the spirit of the invention.

I claim:

l. In a coupling for well logging apparatus, the

combination comprising a body member; a multiple conductor cable extending through the body member, said cablehaving a weight supporting conductor; and a weight supporting member attached to the weight supporting conductor and electrically insulated from the body member, said weight supporting member being compressively loaded and transmitting the weight associated with said coupling to the weight supporting conductor of said cable.

2. In a coupling for well logging apparatus the combination comprising a body member, a multiple conductor cable extending through the body member, said cable having a weight supporting conductor, a plug attached to the weight supporting conductor, and an insulating sleeve of electrical insulation interposed between the plug and the body member whereby the weight associated with said coupling is transmitted to the weight supporting conductor through the compressively loaded insulating sleeve.

R. FLA'rFoRn. 

